smb/client: fix possible infinite loop and oob read in symlink_data()

These records connect through source-stated identifiers. Shared identifiers or dates alone do not establish shared exposure, root cause or applicability.

CVE-2026-52967 · Microsoft / collected KEV context

cve-program · CVE-2026-52967

• https://git.kernel.org/stable/c/1cfa2d59f669db28d6292d10ff87ca6837c781b0
• https://git.kernel.org/stable/c/b41598bf54b3fe528994e573df6008f8f4d0a4f4
• https://git.kernel.org/stable/c/cd4b9b662f0fb9aa97ee6bf9034eca76fc6cab23
• https://git.kernel.org/stable/c/97a05b0ae9ea5ec052be2eef0f9cc7ce03501bbb
• https://git.kernel.org/stable/c/1b9331b16b0ed9414dcf7583d8134bdfeb117aae
• https://git.kernel.org/stable/c/7d9a7f1f96cd617ee9e75bb22217c709038e26b8

No related operational record is retained in the current change model.